String tension adjustment for steel guitars



July 2. 1968 J. J. KELLEY, JR 3,390,600

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7 STRING TENSION ADJUSTMENT FOR STEEL GUITARS Filed Sept. 10, 1965 4Sheets-Sheet 4 J BY 3- Ms M ABSTRACT on THE DISCLOSURE .This inventionrelates to a structure for adjusting the tension of the strings ofguitars through the utilization of a pedal connection to the stringswhich includes a crank attachedto the end of each of the strings with acrank pivoting device connected therewith which permits the crank to bemoved from a normal position to either increase or decrease the tensionon the particular controlled string when a pedal is depressed. The crankcontrolling mechanism includes a spring arrangement which permits thecrank to be moved to an increasing or decreasing tension" position. Thearrangement of the pedals to control the cranks provides means forattaching a plurality of cranks to any one particular pedal.

A- steel string guitar as known is a generally horizontally, stablymounted guitar unit which is provided with a moveable fret bar formanually selecting chords rather than fingering the strings and whereinthe player plucks and strums the strings much as he would on a standardguitar. The amount of variation in the chordal selection of a steelguitar is of course limited to the skill of the player and the amount oftonal variation attainable by placing the fret bar at various positionsalong the strings. In the past few years, various devices have beenprovided for adjusting the tension and thus changing the pitch of anyone of the strings of these guitars and it is an object of thisinvention to provide a new and unique tuning structure for steel guitarswhich will enable the user to adjust the tension of strings and thusalter the tone of the strings at his greatest ease and permit a greatamount of flexibility in such tone control.

Generally the previously used tension adjustment structures for steelguitars considered consisted of pluralities of steel cables designed toeitherincrease or decrease the tension of any one of the various stringsof the guitar by pulling directly thereon such that the tone of thetightened or -relaxed string would be varied. These cable systemsrequired a complex mechanical hook-up in order to attain both theincrease and decrease of tension, which is required to change the toneof the string both upwardly and downwardly of the musical scale. Onedifficulty in such a tension adjusting device arises when the user orplayer wants to increase the tension on one particular string on onebeat or stroke of the guitar while decreas- United States Patent O ingthe tension on another string and obtaining this action through shiftingonly one control pedal or lever. Naturally this type of arrangementrequires a dual hookup to a plurality of strings and most of themechanical actions to attain this hook-up presently available and usedon guitars are indeed complicated and cumbersome.

Applicant however through the design of the device described hereinprovides means for changing the tuning of the strings of a guitar whichis accomplished with particular ease through the arrangement of multiplecontrols on any one string of the guitar such that it is possiblethrough manipulation of the control pedals provided to decreaseorincrease the tension on any one string through its longest possibletonal range. The system as further provided by the applicant provides apositive action as compared to the previously used cables which includeda "ice certain amount of stretch inherent to a cable operated device andthus the tonal effect or tonal change achieved by applicants device willbe more accurate than such cable controlled devices.

The device provided herein by applicant provides a multiple hook-up orcontrol on any or all of the strings such that any or all of the stringsmay be put through their greatest range of change simply by manipulationof the various control pedals. This is to say that the structureprovided by applicant will permit the change of a pitch of any oneparticular string from its point of most tension or highest pitch to thepoint of most relaxed or lowest pitch attainable in accordance with thespecific size of the string. This multiple hook-up arrangement thenprovides a certain degree of flexibility heretofore unattainable in suchsteel guitar tension adjustment devices while providing this adjustmentin a very simplifiedarrangement which will enable a device to be used bythe ordinary guitar player without requiring a high degree of mechanicalskill.

Further as provided herein by applicant, a certain finger-tip maximumadjustment control is provided for each of the strings Which will permitthe various adjustments to be achieved on each string with a relativelysimple movement. It is only necessary with applicants device to set aninitial maximum setting through a first adjustment mechanism and to tunethe string either tonally upwardly or downwardly from the maximumsetting by coordinating certain other stop features of the unit.

In order to obtain an extreme degree of tonal flexibility applicant hasprovided a unique lever arrangement which provides a double pivotalaction for the attached string unit. This is to say that he providesessentially a free floating lever system wherein the application offorce to one end of the lever will provide one distinct movement eitherupwardly or downwardly to increase or de crease the tension and thustone of a string while a subsequent force applied to the opposite end ofthe lever will absolutely reverse this string action without requiringany complicated mechanical linkages to attain this mechanical shifting.

In order to utilize the complete adjustability of applicants device aunique string resting feature has been provided which will permit therequired adjustments to the string including the repeated stretching andrelaxing of the string without substantially decreasing the strength ofthe string. Further incorporated into this unique string attachmentdevice is a rapid attachment structure which permits insertion orremoval of a string with a minimum ofdifficulty to the player. Further,this particular string holding mechanism also incorporates a settingdevice which controls the maximum tension placed on a string andtherefore serves a dual purpose.

It is therefore an object of applicants invention to provide a new andunique string tensioning device for use with steel guitars and otherstring instruments wherein the pitch of a single or various strings maybe altered to the players desire.

It is a further object of applicants invention to provide a new andunique system for adjusting the tension on the strings of steel guitarwhich includes a unique lever system wherein the lever is substantiallya free floating system wherein pressure on one end of the lever willproduce a reaction in one direction and pressure on the other end of thelever will produce an opposite reaction while holding the lever fromshifting in an undesired direction. V

It is a further object of applicants invention to provide a new andunique tension adjusting device for string guitars or the like whichincludes a means to'positively limit the maximum increase or decrease intension on a guitar and includes devices for limiting the extension ofsaid string ntermedate the maximum tension positions.

It is a further object of applieants invention to provide a new andunique string fastening device for use with a steel guitar wherein thestring is easily fastened thereto and wherein a certain portion of thedevice includes a maximum tension setting unit to limit the amount oftension being placed on any one of the strings.

It is a further object of applicants invention to provide a freefloating lever device for increasing or decreasing the tension on aguitar string or the like which includes a free floating lever memberwith means to apply forces to either end of said lever whereby certainrestraining forces are automatically applied to the opposite end of saidlever such that the tension on the string may be either increased ordecreased at the players desire.

It is a further object of appl-icants invention to provide a stringtensioning device for steel guitars and the like which includes apositive linkage system which is easily shiftable and which permits amultiple tune or pitch change on any one of the strings of a steelguitar which change is achieved through a minimum of difficulty andwherein the change is made to positively locate the pedals of the unitwith respect to one another such that the pedals of the unit will all beactive at a certain level.

It is a further object of applicants invention to provide a stringtensioning unit and thus a pitch adjustment unit for steel guitars orthe like wherein solid stopping situations are provided for each of thevarious control pedals of the unit such that upon attaining said solidstopping portion, the player will know that the string is at its propertonal tension.

It is a further object of applicants invention to provide a tonaladjustment for steel guitars and the like wherein a multiple of tonalchange elements may be mounted on a single control member of a guitarstring wherein actuating different of such elements will provide thedesired tonal effect without incorporating and without aifecting theother various changes available to the strings of the guitar.

These and other objects and advantages of my invention will more fullyappear from the following description made in connection with theaccompanying drawing, wherein like reference characters refer to thesame or similar parts throughout the several views, and in which:

FIG. 1 is a plan view showing a double necked guitar unit incorporatingthe concepts of applicants invention;

FIG. 2 is a front elevational view of the unit as shown in FIG. 1;

FIG. 3 is a vertical section taken substantially along line 33 of FIG.2;

FIG. 4 is a bottom plan view of the unit embodying the concepts ofapplicants invention and illustrating the control features on onlycertain of the strings;

FIG. 5 is a portion of FIG. 4 drawn on to an enlarged scale showingparticular details of the actuator portion thereof;

FIG. 6 is a vertical section taken substantially along line 6-6 of FIG.5 and drawn to an enlarged scale to illustrate the string controlportion of the unit;

FIG. 7 is a partial section taken substantially along line 7-7 of FIG.6;

FIG. 8 is a partial plan view taken along line 88 of FIG. 6;

FIG. 9 is a vertical section taken substantially along line 9--9 of FIG.5.

In accordance with the accompanying drawings, the steel guitarspresently available and as particularly illustrated in FIGS. 1 and 2include at least one of the string sections S as illustrated with theadjustment portions A at one end thereof designed to capture and holdone end of the strings of the guitar with certain adjustment screwswhich are commonly known provided thereon to provide for an initialtuning arrangement of the unit. These basic structures are ordinarilyarranged in pairs and are mounted on a basic mounting board B. The otherend of the string structure includes a means for attach-ing the end ofthe strings thereto and in this case this attaching element is referredgenerally to as C.

Those skilled in the art will recognize that various features in orderto accomplish the playing and amplification of the string unit arenaturally provided on these guitars and these devices are notparticularly described herein as these devices are thought to becommonplace and well known by anyone associated with such musicalinstruments.

Certain additional elements provided in tunable steel guitars arelikewise provided in applicants device and ordinarily the mounting boardB is supported by a plurality of legs L on the ends thereof which legsare arranged to mount and position a pedal mounting board P.

In order to understand the function of this unit, the musical conceptsof this unit are as follows. An initial tuning of the strings must bemade which, for example, on a ten stringed instrument could be G sharp,E, B, G sharp, F sharp, E, D, B, G sharp and E. Various of these stringson a guitar are either what are commonly known as steel or wound stringsand the possible adjustment attainable with the device provided hereinis figured in coordination with the possible increasing or decreasing oftension permitted and recommended for steel or wound strings. As forexample, it is possible with this unit to raise the initial G sharpstring, which is a steel string to A or likewise possible to raise thefirst E to an F or an F sharp key. Continuing from the tuned strings asmentioned above the possible raises for the strings could be as follows:B to a C and to a C sharp and the next adjacent G sharp string to an A,a B flat or a B. In other words, it is possible to raise most of thewire wound strings three /2 tones and to raise at least most of thesteel strings at least a minimum of two /2 tones. This is, of course, tosay that two /2 tone raises will produce a total shift of one wholetone.

Likewise the object of this invention is to provide a means to lowerthese similarly arranged strings to at least an additional tone lowerthan that originally tuned on the unit. For example, in a move to lowertuning it would be possible to lower the G sharp to a G, the E to an Eflat and thence to a D, or the B to a B flat and thence to an A, andthence to an A flat. The possible extremes of this tonal adjustment iscontrolled purely by the fact of the guitar string being either a plainsteel string or a wire wound string but with the structure as providedherein it is possible to attain on each of the strings a maximum ofthree /2 tone changes which is to say that three half tones or a totalof one and a half otnes shifting either upwardly or downwardly ispossible on any of the strings.

The primary apparatus provided herein to obtain the string tensionchange includes a unique free floating lever unit designated in itsentirety 11 which includes a mounting block 12 securely atached to thebottom of upper mounting board B and extends transversely across thewidth of one of the string units S. A plurality of mounting slots 13 areprovided in spaced relation across the block 12; the number of slots 13corresponding to the number of strings on the guitar unit, said slotsbeing of a width to mount a lever bar 14 therein.

In the form shown, as best illustrated in FIG. 6, the lever bar 14 isarranged normally to the mounting bar B and has an upper 14a and lowerend 14b to which the various elements actuated thereby will be attached.A pair of actuating rod members 15-16 are arranged for slidingreciprocatory movement through apertures in block 12 which apertures arein communicating alignment with the mounting slots 13. A linkagereceiving end of the rods 15a-16a extends outwardly from the block 12and is provided with a pair of threaded capturing elements 17a-17b,18a-18b for mounting a hook element 19-20 therebetween which hookelement 19-20 will receive certain actuating linkages from the pedalsystem to control the movement of lever 14.

I 4 5 'As illustrated in FIG. 6, rod is pivotally attached to lever 14intermediate the ends thereof while rod 16 is attached adjacent end 14bthereof. A holding spring member 21 is attached at one end to end 14b oflever '14 and is attached to a portion of the mounting board B through athreaded adjustment member 22. Adjacent end 14a of lever 14 a primaryconnector member in the form of a pivotally mounted link 23 on lever 14with means such as a stop enlargement 23a on the extending end thereofis provided KfOl' actuating attachment to the crank string shiftingmechanism generally designated 24.

7 In the form shown each of the string shifting mechanisms 24 areindividually pivotally mounted for rotation upon an axle 25,the ends ofwhich are mounted onto the mounting board B through stationary capturingele- I ments 26-26. Crank structure 24 is of course commonly known andincludes a pair of arms extending at an angularly relation. One arm 27of said crank 24 extends generally parallel to board B and overlies anabutment plate 28 provided on the end of board B. This arm 27 includesa. first adjustment member 29 with a locking member 30 arranged normallythereto. Adjustment member 29 extendsgenerally vertically through arm 27to be in approximate abutting relation to block 28 and as should beobvious, varying the exposure of adjustment member 29 through arm 27will limit the movement of crank 24 about axles '25 in one rotativedirection. This structure then is the adjustment to govern the maximumstretching of the strings and thus control the upper limit of their tunechange.

" String end S is held to arm 27 through a unique capturing device whichincludes an enlarged stop 32 secured on the end of the string 8 whichstop will be received into an arcuate passage 33 formed angularlythrough arm 27 and wherein the string 8 will be received into asubstantially smaller communicating slot 34 which slot 34 will notpermit the enlarged portion 32 to pass therethrough. This stringattachment system also provides a quick change string release in that itis only necessary to substantially release the tension on the string Ssuch that the enlarged end of the string 32 may be removed upwardly fromthe angularly arranged passage 32.

The other end 35 of the crank 24 extends downwardly through an opening36 formed in the mounting board B and has a slot 37 formed therethroughto receive a portion of the linkage 23 therein to thus abut with theenlarged portion 23a thereof. From this construction it should beobvious that the shifting of the lever structure 14 will either permitthe crank 24 to rotate in one direction which direction is due to theintal tautness of the strings or pull the crank 24 in a stringtightening direction. I

In order to provide a limit to the downward tonal change which isdecreasing the string S tension a structure is provided .to control andlimit the movement of rod 16 and in the form shown this structureincludes .a stop member 40 including an eye 40a portion on one endthereof tobe received about engagement hook with means for adjusting theother end thereof with respect to the frame portion of board B includinga screw element 41, an internally threaded member 42 to receive thescrew and a spring between the board B and member 42 to hold member 42for adjustment.

When the downward tone change of the strings is desired rod 16 will bepulled in the direction of hook 20 through links to be describedhereinafter and thus the lever 14 will revolve about the now stationaryrod 15 to allow the crank 24 to be shifted upwardly due to the tendencyof the tuned, stretched string to return to unstretched condition. Thelimit of this shifting is achieved by properly locating the eye 40a of astop 40 withrespect to the book 20 by adjustment of screw 41. Whenpressure is released from the rod 16 spring 21 will serve to return thelever 14 and crank 24 to its normally tuned position. A partial coverplate 43 is pro- 6 vided to properly hold the stop elements 40 on thehooks 20.

The action of the unit 11 when the player wishes to increase the tensionon the string is to apply a force upon rod 15 tending to draw the rod 15in the direction of hook 19 thus now permitting lever 14 to rotateaboutthe now stationary rod 16. In this situation the arms of the crank 24will be pulled downwardly limited only by stop 29 and upon release ofthis actuating force the normal tension of the string S will return thestring to its normally tuned position.

To provide the actuating force to the lever block 12 and associatedlever 14 applicant illustrates the ordinary pedal structure P whichincludes a pedal mounting rod 45 to which the various pedals 46 areattached. Vertically extending rods 47 are provided for actuation by thepedals 46 and in the form shown are provided with turn buckle adjusters47a to permit adjustment to facilitate locating all of the pedals in oneplane. Below the mounting board B the structure for attaching the pedalsto the rods 15-16 is shown and in the form shown consists of a pluralityof transversely extending rod mernbers 51 having their ends mounted forrotation in housings 5253 arranged longitudinally of the mounting boardB. To permit removal and change of these rods 51, applicant providescertain portions of the capturing housings 52 to be segmented such thatthe bottom half portion 52a as illustrated in FIG. 3 may be removed andthe respective rods 51 slid from housing 53 and lifted from the mountingassembly.

In the form shown each of the rods 51 includes a first fixedlyattachedarm 55 to receive an upper hook element 48 of the pedal linkage member47 and these first bars 55 are arranged generally horizontal foractuation by the pedals 55. A stop member 5511 may be provided on themounting board B such that upon release of a pedal E no noise will beheard when the bar 55 is returned to its normal position.

The actual control linkages controlling rods 15-16 are illustrated inthe various views but for simplicity all of the possible linkages forthe tonal changes have not been illustrated and therefore in thefollowing discussion it should be obvious that each of the structuresdisclosed could be placed on each of the available bars 51 to provideadditional linkage elements.

In order to achieve the shifting of the rods 15-16 of adjustment block12, second generally vertically extending The apertures 56111 areprovided for proper stretching of the strings S as various of thestrings S are naturally larger in diameter than others and of necessityrequire a greater degree of stretch in order to properly shift the tone.In the form shown these attachment links generally designated 60 eachinclude a hook 61 on one end to be received into the finger elements 56and an eye element 62 on the other end thereof for engagement witheither hook 19 or hook 20 depending upon the effect wanted from eachpedal. In the case of dual control desired from any one pedal, aU-shaped intermediate attachment member may be provided for attachmentto the initial control finger 56; said U-shaped member 63 then providingat least two possible apertures for receiving the hook element 61 of thelinks 60. A triple hook-up likewise is attainable with this unit and oneof said triple links is shown in FIG. 5 wherein two of the U-shapedelements 63 are connected. Likewise additional multiple hook-ups areattainable but each additional string connected requires additionalpower to depress the pedals.

In order to provide the proper adjustment of the links 60 each of thelinks 60 is provided with a turn-buckle type portion 64 which willeliminate any longitudinal play in the links 60. Likewise in order toprovide the best action the finger members 56 are slidable on rods 51 toattain a straight line relation for the links 60 connecting the levers14.

Control for the maximum 3-shift tonal effects as previously stated, liesin the adjustment screw 29 on crank 24 and the positioning of eye 40a onadjustment member 40 through screw 41. The player in using thisinstrument may want to change any specific string either upwardly ordownwardly three steps. To do this he will pick the maximum step desiredand set this through the appropriate adjustment on screw 29 or screw 41.Now if it is desired to play either or both of the two steps betweenthis maximum adjustment an additional adjusting feature is providedherein. In the form shown a bar member 70 is provided longitudinallybelow the mounting board B intermediate the ends of rod 51 and a thirdarm 71 is provided on each of the rods 51. This particular structure isshown more specifically in FIG. 9 wherein the shape of the bar 70 isshown provided with a plurality of threaded passages 70a therethroughcorresponding to the location of arm 71 and a relief opening 70b isprovided in mounting board B directly therebelow. A thumb screw 72 orthe like is provided to be received through a clearance aperture in arm71 and threaded aperture 70a whereby the maximum rotation of the rod 51will be controlled through abutment of arm 71 with the head of the thumbscrew 72.

At this point it should be stated and should be obvious that it ispossible to control either one of the bars or 16 through a plurality oflinkages 60 received about the respective hooks 19-20. Thus for example,should the player wish to have a three step change in one tonaldirection it is necessary to attach three of the linkages 60 to one ofthe hooks 19 or 20. Then it should be obvious that having set themaximum control through adjustment members 29 and 41, the intermediatecontrol steps would be set by adjusting two of the stop devices 72 onthe other two controlling links 60' on this single hook 19 or 20.

The device as disclosed herein permits complete flexibility for theplayer as he may easily shift any of the controlling linkages 60 tocontrol the proper string and the flexibility likewise includes thepossibility of one pedal controlling any number of such strings and thiscontrol includes either loosening or tightening or a combination thereoffor any of the strings.

It should be obvious that applicant has provided a new and unique tonalarrangement for steel guitars or other stringed instruments which willallow complete range of flexibility in adjusting the tension on thestring while providing a mechanical arrangement to attain this effectwhich is extremely simple and unique in its operation.

It should, of course, be understood that various changes may be made inthe form, details, arrangements and proportion of parts withoutdeparting from the scope of my invention, which generally statedconsists in the matter set forth in the appended claims.

What I claim is:

1. A device for selectively increasing or decreasing the tension on thestrings of a steel guitar to change the tones of the strings thereof,the guitar including a string section mounted on a mounting board, saiddevice including:

(a) a plurality of individual shifting means arranged to engage one endof each of the guitar strings including a crank mounted for rotationabout an axle, the string being attached to one of the arms of saidcrank;

(b) actuator means operatively connected to said shifting means toproduce rotation of said crank to selectively increase or decrease thetension on said string including:

(1) a plurality of rotatable rod members mounted transversely along saidboard;

(2) a free floating lever system having a plurality of levers arrangedto control the shifting of said crank members each of said lever memberspivotally mounted on a pair of actuator connector members to permitrotation thereof about one actuator member when the other such actuatormember is moved;

(3) linkage means connected to said rods and said actuator connectormember for selective actuation of said levers to control the directionof movement thereof; and

(4) means for rotating said rods whereby said levers are shifted inaccordance with the rotation thereof to produce the proper rotation ofsaid string controlling crank.

2. The structure set forth in claim 1 wherein said lever system includesa mounting block member having said levers arranged therein each of saidlevers being pivotally provided with said pair of actuating connectormembers mounted for sliding movement through said block, said linkagemeans being connected at one end thereof to said rotatable rods and atthe other end thereof to one of said sliding connector members wherebyrotation of said rod in one direction will shift one end of the lever,the other end of said lever pivoting on said other connector memberwhereby the lever efiiect will be reversed in accordance with theactuation of one of the connector members to produce the proper rotationof said crank to thus increase or decrease the tension of the attachedstring.

3. The structure set forth in claim 2 wherein said mounting blockincludes a plurality of lever receiving guide slots to preventtransverse movement of the lever and said passages are provided throughsaid blocks to communicate with said slots.

4. The structure set forth in claim 3 wherein said connector members areprovided with hook elements on the ends opposite the lever engaging endsto receive and capture the linkage members thereon.

5. The structure set forth in claim 3 and return means including aspring member are provided on the ends of the respective levers oppositethe crank attachment end to return the lever to a normal position.

6. The structure set forth in claim 3 and adjustable stop means engagingat least one of said connector members to limit the shifting of saidfree floating lever thereby.

7. A string guitar including:

(a) a mounting board;

(b) a string section having a plurality of musical strings mounted onsaid board with means to tune said strings on one end of said strings;

(c) a crank member removably secured to the other end of each of saidstrings, said cranks being mounted for rotation on said board with onearm of said crank extending below the surface of said board;

(d) an actuator operatively connected to said cranks to control therotation thereof including:

(1) a plurality of lever members having one end thereof respectivelycontrollably connected to each of said cranks;

(2) a pair of actuating rod members, one of said rods pivotallyconnected to said lever intermediate the ends thereof, the other of saidrods pivotally connected to said lever adjacent the other end of saidlever; and

(3) means for selectively actuating one of said rod members to producerotation of said lever about the other of said rod members whereby therotation of said crank will be controlled to iu crease or decrease thetension on one of the guitar strings.

8. The structure set forth in claim 7 and stop means are provided tolimit the rotation of each of said cranks whereby the maximum tensionchange thereof may be limited.

9. The structure set forth in claim 8 wherein a plurality of actuatingmeans may be operatively connected to one of said rod members andadjustable stop means provided for each of said actuating means to limitthe movement thereof to-thereby limit rotation of the connected crank asit is rotated from a normal position to a position of maximum tensionchange whereby a plurality of tones may be sounded from any of saidstrings in accordance with the permitted movement of the selectedactuating means.

10. The structure set forth in claim 7 and each of said strings providedwith an enlarged stop member on the crank engaging end thereof saidcrank providing a quick release mechanism for retaining said enlargementstops.

11. The structure set forth in claim 10 said quick release 10 includinga passage angularly through one arm of said crank to receive the stopenlargement therein and a slot member communicating with said passagereceiving the string therein but preventing the passage of saidenlargement therethrough.

References Cited UNITED STATES PATENTS 2,531,569 11/1950 Hise et al.84297 2,654,283 10/1953 Barr 84-312 2,973,682 3/1961 Fender 842973,136,198 6/1964 Smith et a1 84--312 RICHARD B. WILKINSON, PrimaryExaminer.

LAWRENCE R. FRANKLIN, Assistant Examiner.

